<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script>
        var app = 18;
        var App = 100;
        console.log(app);
        console.log(App);
        //尽量不要用name作为变量名
    </script>
</head>
<body>

</body>
</html>